Agrococcus carbonis sp. nov., isolated from soil of a coal mine.

An actinobacterial strain, designated G4(T), isolated from a coal mine was subjected to polyphasic taxonomic characterization. Cells were Gram-stain-positive, yellow-pigmented, non-motile and non-spore-forming cocci. This organism possessed a type B peptidoglycan with diaminobutyric acid as diagnostic diamino acid. The major respiratory quinones were MK-9, MK-10 and MK-11. The major fatty acids were anteiso-C(15 : 0) (41.6 %) and anteiso-C(17 : 0) (32.8 %). The predominant cellular polar lipids were diphosphatidylglycerol and phosphatidylglycerol. Cell wall sugars comprised galactose, glucose, ribose and rhamnose. 16S rRNA gene sequence analysis of strain G4(T) showed high similarity with Agrococcus baldri (98.9 %), Agrococcus citreus (97.8 %), Agrococcus jenensis (97.3 %) and Agrococcus terreus (97.0 %). Sequence similarity with the type strains of the other species of the genus Agrococcus was less than 97.0 %. The DNA-DNA relatedness of strain G4(T) with the type strains of Agrococcus baldri, Agrococcus citreus, Agrococcus jenensis and Agrococcus terreus was less than 70 %. On the basis of the physiological, biochemical and chemotaxonomic characteristics, strain G4(T) should be classified as the type strain of a novel species of the genus Agrococcus, for which the name Agrococcus carbonis sp. nov. is proposed. The type strain is G4(T) ( = MTCC 10213(T)  = DSM 22965(T)).